Epoll and IO Multiplexing

August 15, 2021 · 834 words · 4 min · OS Linux Network IO

Let’s start with epoll. epoll is an I/O event notification mechanism in the Linux kernel, designed to replace select and poll. It aims to efficiently handle large numbers of file descriptors and supports the system’s maximum file open limit, providing excellent performance. Usage API epoll has three primary system calls: /** epoll_create * Creates an epoll instance and returns a file descriptor for it. * Needs to be closed afterward, as epfd also consumes the system's fd resources.

HTTPS Introduction

February 21, 2021 · 564 words · 3 min · Network HTTPS HTTP

HTTPS (HTTP over SSL) was introduced to address the security vulnerabilities of HTTP, such as eavesdropping and identity spoofing. It uses SSL or TLS to encrypt communication between the client and the server. Problems with HTTP Communication uses plain text, making it susceptible to eavesdropping. Unable to verify the identity of the communication party, making it vulnerable to spoofing (e.g., Denial of Service attacks). Cannot guarantee message integrity, making it possible for messages to be altered (e.